For years, the automotive industry has been buzzing about hydrogen fuel cell technology as an alternative to gasoline, but automobile manufacturers have yet to make it a reality for consumers. The materials handling industry, on the other hand, is leading the way to successfully implementing hydrogen fuel cell technology in electric lift trucks; and this new technology is quickly becoming a viable alternative to lead-acid batteries.
Although ongoing research continues to evaluate the benefits of using hydrogen fuel cell technology over electric batteries, fuel cell-powered lift trucks are already becoming commercially available. Now more than ever, it is crucial that managers in food processing and manufacturing facilities thoroughly understand and seriously evaluate this new technology to determine if it's right for their operations.
Fuel cell 101
A fuel cell is an electrochemical energy conversion device. Energy is stored as hydrogen gas and converted into electricity as needed. By converting the chemicals hydrogen and oxygen into water, hydrogen fuel cells produce electricity. Unlike other power methods, such as internal combustion engines, there is no pollution as a result of the process, as the only by-products generated are water and heat. Hydrogen is a readily available industrial gas that can be shipped from a hydrogen manufacturer to facilities via truck in liquid or gas form, or it can be generated on site. Either method requires special equipment to compress the gas to the specific pressures needed to fuel lift trucks. In addition, a hydrogen dispenser is needed to rapidly fill the lift truck's fuel tank. In order for fuel cells to successfully function in lift trucks, numerous companies including hydrogen suppliers, fuel cell suppliers and lift truck manufacturers have been working together to research the application of this technology.
Why fuel cells?
While the development of fuel cell technology in lift trucks is still in its infancy and may currently be cost prohibitive for most facilities, it has the long term potential to generate significant cost savings through longer lift truck run times, lower maintenance costs and the elimination of battery-charging infrastructure - especially in high throughput applications.
Presently, the materials handling industry is comfortable with lead-acid batteries. The technology is reliable and is readily available from multiple suppliers. Batteries also provide the necessary counterweight in lift trucks and are readily removable when their energy is depleted. However, lead-acid batteries will typically only last one shift in a high-use application and the recharge cycle is long, as batteries generally take one shift to charge and another to cool down. Thus, in a three-shift operation, three or more batteries plus a charger may be needed, in addition to the room it takes to store and recharge them.
Conversely, hydrogen fuel cells offer the potential for higher productivity simply because they can be rapidly refueled. To restore energy, the lift truck operator would drive the vehicle to one of many hydrogen refueling stations located around the facility and refuel the tank with hydrogen in minutes, completely eliminating the time it takes to recharge and replace a battery. And, unlike a battery powered lift truck where the voltage drops as the battery discharges, the voltage delivered by a fuel cell remains constant until the fuel is depleted. Therefore, the lift truck will not experience performance degradation until the fuel completely runs out. Another benefit to hydrogen fuel cell technology is that it is environmentally clean. The only byproducts are water and heat. This is especially important in food processing and manufacturing facilities where clean air and a clean environment are essential.
Another benefit to the food processing industry is performance in cold storage. Currently, the range and performance of lift trucks with lead-acid batteries is reduced when the units are driven in freezers. However, a lift truck with a fuel cell will maintain its performance since the voltage and current remain the same at cold temperatures.
At the present time, however, fuel cell technology is viewed as complex and cost-prohibitive. Individuals working within facilities must be willing learn the intricacies of the new technology and its associated equipment. This includes learning how to use and handle compressed gas.
Evolution of fuel cell-powered truck design
The current stage of hydrogen fuel cell-powered lift truck design focuses strictly on battery replacement. With a battery-replacement design, the lead-acid battery is removed from the lift truck and replaced with a fuel cell system of the same size, weight and energy capacity. The lift truck has no idea it is being powered by a hydrogen fuel cell system instead of a lead-acid battery. At this stage of the evolution, one method of power is simply "replacing" the other. Fuel cell systems that incorporate battery replacement technology are currently commercially available.
An anticipated next step in the evolving design of fuel cell-powered lift trucks involves modifying the existing lift truck platform so the fuel cell components are distributed in an optimum way around the truck. This design will require very close cooperation between lift truck manufacturers and fuel cell suppliers.
The ultimate evolutionary step in hydrogen fuel cell-powered lift truck design is a clean sheet design. In this optimal phase, a new lift truck will be designed from the ground up with the fuel cell completely integrated into the truck, and the truck will not use a conventional battery as a power source. In this phase, lift truck manufacturers will do most of the development while working closely with a supplier of fuel cell components. As fuel cell technology in lift trucks continues to progress, this evolutionary step is what the materials handling industry may ultimately achieve.
Evaluating the technology
Much like the manufacturing companies, suppliers and associations involved in developing and studying fuel cell technology, managers in food processing and manufacturing facilities can also take the appropriate steps to become educated and to evaluate the technology. Important considerations for facility managers to help better-prepare for the emerging technology are:
• Talking to lift truck dealers or manufacturers about fuel cells to find out if available units will work with specific fleets.
• Understanding the important issues related to integration, such as electrical and mechanical interfaces, stability and counterweight, and emergency stop.
• Investigating the costs of hydrogen and hydrogen infrastructure and evaluating whether implementing the technology is cost effective.
Though fuel cell technology is still on the horizon in the automotive industry, in the material handling industry, it's already here. Food processors and manufacturers can take advantage of the higher productivity and cleaner running that this technology offers.
